The Biostatistics & Bioinformatics Core (Core 9004) will provide biostatistics, bioinformatics and data management support to subprojects 0001-0004, Core 9002 and Core 9003. Specific aims of the Core 9004 are: (1) to provide data management support for Projects 0001-0004, Core 9002 and Core 9003; (2) to provide biostatistics and bioinformatics support to Core 9003 and microarray experiments proposed under Projects 0001, 0003 and 0004, and; (3) to provide biostatistical and mathematical modeling support to Projects 0001-0004. Under Specific Aim #1, Core 9004 will develop a PPG web portal, data storage, data use policies including data sharing and publishing. The PPG web portal will streamline data entry, verification, storage, and retrieval across four projects and cores. Under Specific Aim #2, Core 9004 will develop and implement a pre-processing and normalization protocol for Core 9003 as well as bioinformatics tools to efficiently retrieve and mine biological information from public databases. Further, Core 9004 will provide statistical analysis support for the microarray experiments and provide consultation on the design and analysis of the RT-PCR confirmation experiments. Under Specific Aim #3, Core 9004 will provide data analysis support for all experiments proposed under Projects 0001-0004 and assist the investigators with data interpretation and manuscript preparation. Core 9004 will develop mathematical and statistical models if necessary and incorporate recently published methods such as the analysis of lymphocyte kinetics and turnover.